Data Library

The goal of the Data Library is to provide a suite of layers which are managed by the SeaSketch team and can be easily added to any project. Making a map portal should be super easy in SeaSketch. The data should either be:

1. Already available in SeaSketch
2. Easy to add from a data service, or
3. Easy to upload and style

The Data Library tackles the first part of that formula.

Architecture

Data Library entries can take many forms. There is a taxonomy of these items, and each is going to be implemented a little differently.

1. Entries which are a single, or group of multiple, table of contents items. (Coral Reef Watch being the first)
2. Entries which are a basemap (Global Fishing Watch)

Table of Contents Items

In the case of our first use-case, NOAA Coral Reef Watch provides a set of layers as NetCDF files (+ a kml) which are updated on a web directory approximately data. The general pattern supporting this Data Library item is as follows.

1. A folder, containing table of contents items representing each of these layers is manually created in the superuser project. This includes creating the initial cartography, metadata, attribution, and interactivity.
2. Manually in the database, table_of_contents_items.data_library_template_id is set on each item with a unique identifier, such as "CRW_ROOT" for the root folder, and "CRW_BAA" for the BAA (bleaching alert level) layer.
3. An update job is created as a graphile_worker task which runs like a cron job when setup in the server configuration. These tasks take advantage of a common set of utilities for writing data library update tasks, and store metadata in table_of_contents_items.data_library_metadata to keep track of versioning and update dates between what's on SeaSketch and what is on the authoritative source's website. These utilities use the "replace data source" workflow and lambda already used to support data upload versioning in order to update data library templates. Code in the replace_data_source stored procedure identifies project copies of Data Library items, and also keeps them up to date when the template source changes.
4. Once there are ID'd layers in the superuser project, and infrastructure to support keeping them up to date, they can be added to the client in DataLibraryModal.tsx, referencing the root template ID to be copied into the destination project.